以二硫化錫薄片製備之壓電奈米發電機應用於生物力學能量收集與智能人機介面

Abstract

二硫化錫奈米薄片 (SnS2 nanosheets, SnS2 NSs) 在分類上屬於二維層狀金屬二硫族化物 (layered metal dichalcogenides, LMDCs)，由於其出色的載子遷移率、化學穩定性及光電特性，使得其在眾多領域應用中引起了相當廣泛的關注，其中即包含了超級電容器、太陽能電池、光電感測器、催化反應和場效電晶體等等。與此同時，亦有理論計算指出二硫化錫奈米薄片具有優於其他同是層狀金屬二硫族化物之壓電常數，據此結論推知，其對於未來壓電元件之開發具備極大潛能。然而，迄今為止，對於二硫化錫的壓電特性仍無相關的實驗性數據與文獻發表。因此在本研究中，我們將探討由化學氣相沉積法 (chemical vapor deposition, CVD) 成長之高品質、低層數二硫化錫奈米薄片之壓電特性，並首次透過壓電力顯微鏡 (piezoresponse force microscope, PFM) 量測得二硫化錫薄片之壓電響應，同時根據量測結果，計算出二硫化錫奈米薄片之面外壓電常數 (d33) 約為5 pm/V。此外，我們亦將所合成之二硫化錫奈米薄片製作成壓電奈米發電機 (piezoelectric nanogenerator, PENG)，並展示其應用於自供電技術和應變感測器的潛力。最重要的是，二硫化錫壓電奈米發電機可有效地整合入人機介面同步系統，顯示了其在未來先進人機介面應用、智慧語言系統和遠程互動中的可行性。

Tin disulfide nanosheets (SnS2 NSs), belonging to the family of two-dimensional layered metal dichalcogenides (LMDCs), has attracted considerable attention in multidisplinary scientific applications owing to their outstanding carrier mobility, chemical stability, and electronic properties. These applications include SnS2-fabricated supercapacitors, solar cells, photodetectors, catalytic reactions, and field-effect transistors. Meanwhile, some theoretical predictions also point out that SnS2 possesses a relatively large piezoelectric constant, indicating its great potential to convert mechanical to electrical energy. To date, however, only very few attempts have been made to investigate the electromechanical characterisitcs of SnS2 nanosheets. Herein, we report, for the first time, a study to investigate the piezoresponse of SnS2 nanosheets produced by a chemical vapor deposition (CVD) method. The linear piezoresponse of SnS2 nanosheets was obtained via piezoresponse force microscope (PFM) measurements, where the out-of-plane piezoelectric coefficient (d33) of SnS2 nanosheets was estimated to be 5 pm/V. Moreover, the derived SnS2 nanosheets were integrated into an piezoelectric nanogenerator (PENG) device for the self-powered systems and strain sensing applications. Most importantly, the as-fabricated SnS2 PENG devices can be effectively applied to a human-robotic synchronous system, demonstrating its feasibility for the future advancements in human-machine interface applications、smart language systems and remote interactions.